In recent years, many devices that have the ability of accessing the Internet, which is an external network, have been developed as electrical home appliances, with the recent progress of semiconductor technology. For example, contain types of TV receivers incorporate a high-performance central processing unit (CPU). Hereinafter, this kind of TV receiver will be referred to as Internet TV receiver. The Internet TV receiver accommodates therein a CPU and a modulator-demodulator (hereinafter referred to as modem). Thus the Internet TV receiver is not only able to receive TV programs in common with conventional TV receivers, but also able to access Internet servers. The Internet TV receiver is thus capable of utilizing information services for browsing a package of one or more files including downloadable software programs, and others of documents, voices, pictures, etc. which are provided through WWW (World Wide Web) servers, electronic mail services through Internet, etc. In this specification, the package and the electronic mail data will be simply referred to as Internet information.
FIG. 14 shows a configuration of conventionally contemplated Internet TVs. In FIG. 14, TV signals carried by broadcast waves are received through a receiving antenna 10. The input signal is applied into a tuner 12 for a channel selection and a demodulation of signals of the selected channel. Baseband signals obtained by the demodulation comply with, for instance, the NTSC format in Japan. The baseband signal is applied to an NTSC decoder 13 for decoding therefrom a luminance signal and a chrominance signal.
A conventional TV receiver is in the structure as described above. In case of Internet TV receivers, there is provided a display mode changer 14 for selectively displaying a conventional TV program or an image which corresponds to Internet information. When a TV receiver is set in the mode to display conventional TV programs, the display mode changer 14 selectively introduces the luminance signal or the chrominance signal from the NTSC decoder 13 to an output terminal 15 for displaying it on a display (not shown) connected to the output terminal 15.
On the other hand, Internet information is received to a TV receiver through public lines such as telephone lines etc. ISDN (Integrated Service Digital Network) lines, CATV lines, etc. The Internet information received through an input terminal 21 is applied to a modem 22. The modem 22 is capable of receiving or transmitting data. The modem 22 is connected to a system bus 23 for receiving or transmitting data under the control of a CPU 24. The CPU 24 performs a data processing and a control of associated circuits blocks based on a stored program, i.e., software stored in a memory 25. If decoded data is for display control, the CPU 24 supplies the data to a graphic controller 26. The graphic controller 26 supplies video signals to the display mode changer 14 through a video memory 27. When a TV receiver is set in a mode to display Internet information, the display mode changer 14 selects video signals from the video memory 27 and leads out to a display unit (not shown) via the output terminal 15. Thus, the Internet information is displayed on the display unit.
An input/output interface (I/O interface) 28 is connected to the system bus 23. The I/O interface 28 is possible to perform the channel selection, a picture quality adjustment, a display mode switching, etc.
Further, the system bus 23 is connected with a received optical data processor 29. The received optical data processor 29 receives and processes transmitted from a remote controller 30. Subsequently the received optical data processor 29 is able to change over the system operating functions to modes suitable for the user's operation. The control signal in response to user's operation is supplied to the control ends of the tuner 12, the NTSC decoder 13, the display mode change 14, etc.
In addition, there is such an Internet TV receiver which is provided with a screen combining unit instead of the display mode changer 14 for simultaneous displaying both of TV broadcasting and Internet information on two screens.
Next, the operation of software associated with processing of Internet information by CPU will be described in reference to FIG. 15.
FIG. 15 is a block diagram representing operations implemented by a software for explaining one example of the software operation related to the process of Internet information by a CPU. Operational examples of software are shown, for example, in "INTERFACE", pp. 131-135, issued on June, 1996. FIG. 15 is a flowchart depicting the software as a flow of operations associated with the contents of the publication.
When the circuit is connected to the Internet, the communication protocol process of the modem is executed for Internet information by a modem controller 41 which is equivalent to the modem 22. The output data of the modem controller 41 is transferred to a network processor 42. Normally, the Internet information is transmitted as per a protocol so-called as TCP/IP (Transmission Control Protocol/Internet Protocol). Therefor, the network processor 42 executes processes based on the TCP/IP to extract the Internet information from packets. The extracted Internet information is the applied to an HTTP processor 43.
There are several hundred protocols on the Internet and data of the WWW contents (files existing in servers on the WWW) described in a language called HTML (Hyper Text Markup Language) are exchanged as per an HTTP (Hyper Text Transfer Protocol). The HTTP is a stateless protocol designed for high speed transmission of documents.
Therefore, an HTTP processor 43 extracts HTML from HTTP and then transfer it to an HTML analyzer 44. In the HTML analyzer 44, a grammatical analysis of HTML is executed, prescribed data are decoded and developed data are supplied to a browser 45. The browser 45 arranges and displays the developed data. The actual layout display is achieved by the software process by the CPU 24 and the graphic controller 26.
According to the Internet TV described above, a signal processing system in a mode to display conventional TV program and a signal processing system in a mode to display Internet information are completely independent of each other. Further, there are cases that a user wishes to receive Internet information by connecting to the Internet, for instance, such cases that a user wishes to know detailed information on the cast of a TV program received by the user or a person or when a place wherein Internet information exists is introduced on a TV program by a URL (Universal Resource Locator) type notation ("http://www.Toshiba. . . . ", etc.) or when the user wishes to know detailed information as to an area where the program is filmed.
In these cases, the user needs to access a file on a server linked to the Internet after entering names of the casts, a name of program recording location, URL, etc. on a memo pad, a memory, etc. and entering them into an Internet TV receiver by an entry interface such as a keyboard, etc. There are problems that such an accessing operation is inconvenient for users and Internet information is not instantly received.